JP2003165973A - Mechanoluminescent material - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To obtain a mechanoluminescent material with a high luminous intensi ty. <P>SOLUTION: This mechanoluminescent material comprises a luminescent center consisting of a rare earth metal or a transition metal and a host material consisting of at least one oxide selected from among (A) an aluminousilicate represented by the formula: M<SP>1</SP>O-yAl<SB>2</SB>O<SB>3</SB>-zSiO<SB>2</SB>, (B) an aluminate represented by the formula: xM<SP>2</SP>O-yAl<SB>2</SB>O<SB>3</SB>, (C) a silicate represented by the formula: xM<SP>3</SP>O- ySiO<SB>2</SB>or Ba<SB>2</SB>MgSiO<SB>7</SB>, (D) a tantalate or niobate represented by the formula: xM<SP>4</SP>O-yM<SP>5</SP><SB>4</SB>O<SB>11</SB>, (E) a gallate represented by the formua: xM<SP>5</SP>O-yGa<SB>2</SB>O<SB>3</SB>, and ZrO<SB>2</SB>. In these formulas, M<SP>1</SP>, M<SP>2</SP>, M<SP>3</SP>, and M<SP>4</SP>are each Ca, Ba, or the like; M<SP>5</SP>is Ta or Nb; and (x), (y), and (z) are each 1 or higher. <P>COPYRIGHT: (C)2003,JPO

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a so-called mechanoluminescence material that emits light by applying a mechanical external force.

[0002]

2. Description of the Related Art Conventionally, a phenomenon in which a substance emits visible light or light in the visible region at a low temperature such as room temperature when an external stimulus is applied, is well known as a so-called fluorescence phenomenon. A substance that causes such a fluorescence phenomenon, that is, a phosphor, is used for an illumination lamp such as a fluorescent lamp or a CRT (Cat).
hode Ray Tube) It is used as a display such as a so-called CRT. External stimuli that cause this fluorescence phenomenon are usually ultraviolet rays, electron beams,
It is given by X-rays, radiation, electric field, chemical reaction, etc., but up to now, a material that emits light by stimulus such as mechanical external force is not well known.

[0003]

The present inventors have previously proposed that at least one aluminate having a non-stoichiometric composition should be used.
A substance having a lattice defect that emits light when a carrier excited by mechanical energy returns to the ground state, or at least one selected from rare earth metal ions and transition metal ions in the host substance. High-intensity stress-stimulated luminescent material composed of a substance containing the metal ion of the present invention as the central ion of the luminescence center (Japanese Patent Laid-Open No. 2001-49251)
And a light emitting material containing Y ₂ SiO ₅ , Ba ₃ MgSi ₂ O ₈ and BaSi ₂ O ₅ as a base material (Japanese Patent Laid-Open No. 2000-313878).
However, in order to put these light emitting materials into practical use, the light emitting intensity thereof is not yet sufficient, and those having higher light emitting intensity have been required. Under the circumstances, the present invention has been made for the purpose of providing a mechanoluminescence material exhibiting higher emission intensity.

[0004]

Means for Solving the Problems The inventors of the present invention have conducted diligent research to develop a mechanoluminescent material exhibiting higher emission intensity, and as a result, some aluminosilicates, aluminates, and silicates have been obtained. It was found that a mechanoluminescence material having high emission intensity can be obtained by using a tantalum salt, a tantalate salt, a niobate salt, a gallium salt and zirconium oxide as a base material, and the present invention has been completed based on this finding.

That is, the present invention provides (A) the general formula xM ¹ O.yAl ₂ O ₃ .zSiO ₂ (M ¹ in the formula is Ca, Ba or Sr, part of which is Na, K and Mg). At least one of x, y and z is a number of 1 or more), and (B) a general formula xM ² O · yAl ₂ O ₃ (wherein M ² is Ca or Ba, and a part of Mg is Mg
And La in which x and y have the same meanings as described above), and (C) a general formula xM ³ O.ySiO ₂ (wherein M ³ is Ca Or Sr, part of which is N
a, Mg, Zn, Be, Mn, Zr, Ce, and Nb may be substituted, and x and y have the same meanings as described above) or Ba ₂ Mg.
A silicate represented by SiO ₇ , (D) a general formula xM ⁴ O · yM ⁵ ₄ O ₁₁ (M ⁴ in the formula is Ca, Ba or Sr, M ⁵ is Ta and Nb
At least one of the above, wherein x and y have the same meanings as defined above, and (E) a general formula xM ⁵ O.yGa ₂ O ₃ (wherein M ⁵ is Ca, Ba or Sr, part of which may be replaced by La, and x and y have the same meanings as described above) and ZrO
_At least one selected from the group consisting of at least one oxide selected from ₂ and selected from among rare earth metals and transition metals that emit light when electrons excited by mechanical energy return to the ground state. The present invention provides a mechanoluminescent material characterized by adding the luminescent center of

[0006]

BEST MODE FOR CARRYING OUT THE INVENTION The mechanoluminescence material of the present invention has a structure in which a luminescent center is added to a base material,
As the matrix material, an oxide selected from the above (A) to (E) and ZrO ₂ is used.

The members belonging to this (A) group include, for example, (Ca, Na) (Mg, Fe, Al, Ti).
(Si, Al) ₂ O ₆ , (Ca, Na) ₂ (Al, Mg,
Fe) (Si, Al) ₂ O ₇ (Ca, Na ₂ ) Al ₂ Si ₄ O ₁₂ , (K ₂ , Ca, Mg,
Na ₂ ) ₂ Al ₄ Si ₁₄ O ₃₆ , (K ₂ , Sr, Mg, N
a ₂ ) ₂ Al ₄ Si ₁₄ O ₃₆ , (Na, Ca) Al (Al,
Si) ₂ SiO ₈ , (Na, Sr) Al (Al, Si) ₂
SiO ₈ , (Sr, K ₂ , Na ₂ ) Al ₄ Si ₁₄ O ₃₆ , (S
r, Na) (Mg, Fe, Al, Ti) (Si, Al)
₂ O ₆ , (Sr, Na) ₂ (Al, Mg, Fe) (Si,
Al) ₂ O ₇ , Ba ₂ (Mg, Al) (Al, Si) Si
O ₇ , Ba ₂ Al ₂ SiO ₇ , BaAl ₂ Si ₂ O ₈ , BaN
aAlSi ₂ O ₇ , Ca ₂ (Mg, Al) (Al, Si)
SiO ₇ , CaAl ₂ SiO ₈ , CaNa ₂ Al ₄ Si
₄ O ₁₆ , Sr ₂ (Mg, Al) (Al, Si) SiO ₇ ,
_{Sr 2 Al 2 SiO 7, SrNa} 2 Al 4 Si 4 O 16 , and the like. In addition, the elements in the parentheses indicate those that can be replaced with each other.

Next, those belonging to the group (B) include, for example, BaAl ₈ O ₁₃ , BaMgAl ₆ O ₁₁ and CaL.
aAl ₃ O _7, CaMgAl etc. ₆ O ₁₁ and the like.

Further, those belonging to the group (C) include, for example, Ba (Zn, Mn, Fe, Mg) Si ₂ O ₆ ,
Ba ₂ (Mg, Fe) Si ₂ O ₇ , Ba ₂ BeSi ₂ O ₇ , B
a ₂ MgSi ₂ O ₇ , Ca ₂ BeSi ₂ O ₇ , CaMgSi ₂
O ₆ , CaMnSi ₂ O ₆ , CaZrSi ₂ O ₇ , Sr (Z
n, Mn, Fe, Mg) Si ₂ O ₆ , Sr ₂ (Mg, F
e) Si ₂ O ₇ , Sr ₂ B ₂ SiO ₇ , Sr ₂ BeSi ₂ O ₇ ,
Sr ₂ MgSi ₂ O ₇ , Sr ₂ Na ₄ CeFeNb ₂ Si ₈ O
₂₈ , Sr ₃ Si ₂ O ₇ , SrFeSi ₂ O ₆ , SrMgSi ₂
O _{6 and the} like can be mentioned.

Further, for example, Sr (Ta, Nb) ₄ O ₁₁ belongs to the (D) group,
(E) As a member belonging to the group, for example, SrGa
_{There are 12} O ₁₉ and SrLaGa ₃ O ₇ .

Of these, those with particularly high emission intensity
Is (Ca, Na)₂(Al, Mg, Fe) (Si, A
l)₂O_7,Ba₂Al₂SiO₇, Ba₂MgSi₂O₇, B
aAl ₂Si₂O₈, BaAl₈O₁₃, Ca₂(Mg, A
l) (Al, Si) SiO₇, Sr (Ta, Nb)
_FourO₁₁, Sr (Zn, Mn, Fe, Mg) Si₂O₆, S
r₂(Mg, Al) (Al, Si) SiO₇, Sr₂Al₂
SiO₇, Sr₂MgSi₂O₇, Sr₂Na_FourCeFeNb
₂Si₈O₂₈, SrMgSi₂O₆And ZrO₂Is. This
These oxides are point clouds in terms of crystal structure.

[Equation 1] It belongs to the crystal classification represented by.

When these base materials are doped with luminescence centers, the luminescence intensity can be dramatically improved.
In order to dope the luminescence center, the metal to be the luminescence center is mixed well with the host material, and then 600-
Bake at a high temperature of 1800 ° C. for at least 30 minutes. At this time, if a flux such as boric acid is added, the light emitting characteristics are further improved.

As described above, the rare earth metal or transition metal added to the host material as a luminescent center is for dramatically improving the emission intensity. The rare earth metal or transition metal is The ionization energy is preferably 8 eV or less, and more preferably 6 eV or less.

This rare earth metal and transition metal are unstable 3
It has a d, 4d, 5d or 4f electron shell. Rare earth metals include Sc, Y, La, Ce, Pr, N
d, Pm, Sm, Eu, Gd, Tb, Dy, Ho, E
Examples of the transition metal include r, Tm, Yb, and Lu. For example, Ti, Zr, V, Cr, Mn, Fe, Co, Ni, and C.
Examples include u, Zn, Nb, Mo, Ta, W, and the like. Among the transition metals having an unstable 3d electron shell, preferred are Ti, V, Cr, Mn, Fe, Co, Ni,
Among the transition metals having an unstable 4d electron shell such as Cu, Nb and Mo are preferable, and among the transition metals having an unstable 5d electron shell, Ta and W are preferable. . On the other hand, among the rare earth metals having an unstable 4f electron shell, Ce, Pr, Nd, Pm, Sm, Eu, and
Gd, Tb, Dy, etc.

The suitable one as the luminescent center depends on the base material. For example, as a base material, Sr ₂ Al ₂
Eu is preferable when SiO ₇ or Sr ₂ MgSi ₂ O ₇ is used, and Ti is preferable when ZrO ₂ is used.

The amount of the metal serving as the luminescence center is usually selected within the range of 0.001 to 20% by mass. If this amount is less than 0.001% by mass, sufficient luminescence intensity cannot be obtained, and if it exceeds 20% by mass, the crystal structure of the host material cannot be maintained, and the luminous efficiency is reduced, making it unusable.

The emission intensity of the mechanoluminescent material of the present invention depends on the nature of the mechanical action force acting as an excitation source, but generally, the larger the applied mechanical action force, the higher the intensity tends to be. Therefore, the mechanical action force applied to the light emitting material can be known by measuring the light emission intensity. As a result, the stress state applied to the material can be detected without contact, and the stress state can be visualized. Therefore, it can be expected to be applied to a stress detector and other wide fields.

The mechanoluminescent material of the present invention can be made into a laminated material by providing its coating film on the surface of a heat resistant substrate. This coating film is formed by applying a coating solution prepared by dissolving a compound capable of forming a predetermined base material, for example, a nitrate, a halide or an alkoxy compound in a solvent, to the surface of a heat resistant substrate, and then baking the coating. To be done. The heat resistant substrate is not particularly limited, but its material is, for example, quartz, silicon, graphite, heat resistant glass such as quartz glass or Vycor glass, ceramics such as alumina, silicon nitride, silicon carbide or molybdenum silicide, stainless steel. Such heat-resistant steel, heat-resistant metals or heat-resistant alloys such as nickel, chromium, titanium and molybdenum, cermet, cement, concrete and the like can be mentioned.

[0019]

The present invention will be described in more detail by way of examples, which should not be construed as limiting the invention thereto.

Example 1 A powder of Sr ₂ Al ₂ SiO ₇ was used as a base material, and 0.05% by mass of Eu ₂ O _{3 as a} luminescence center and 10% by mass of boric acid as a flux were added and mixed therein. Then, the mechanoluminescence material was manufactured by firing at 1300 ° C. for 4 hours in an argon atmosphere containing 2.5 mass% of hydrogen. Next, this powder is mixed with an epoxy resin [Str
uers, Specifix-40 (trade name)] 1
A sample was embedded in 00 parts by mass at a mixing ratio of 20 parts by mass and pelletized.

The pellet-shaped sample (Sr ₂ Al ₂ SiO ₇ : Eu) thus obtained was subjected to 1
FIG. 1 shows the change over time in the emission intensity when a mechanical action force of 000 N was applied. This sample emitted intense blue light that was clearly visible to the naked eye.

Further, FIG. 2 shows that this sample (Sr ₂ Al ₂ Si
The results of examining the stress dependence of the emission intensity of O ₇ : Eu) are shown in a graph. According to this result, the emission intensity depends on the stress, and the emission intensity also increases as the load increases. From this, it was found that the magnitude of stress can be evaluated by measuring the emission intensity.

Example 2 In the same manner as in Example 1, a matrix material and a mechanoluminescence material having an emission center shown in Table 1 were produced, and the emission intensity (cps) was measured. The results are shown in Table 1.

[0024]

[Table 1]

Example 3 In the same manner as in Example 1, a matrix material shown in Table 2 and a mechanoluminescence material using europium as a luminescence center were produced and the luminescence intensity (cps) was measured. The results are shown in Table 2.

[0026]

[Table 2]

[0027]

According to the present invention, it is possible to obtain a new stress-stimulated luminescent material that effectively emits light by a mechanical external force such as a frictional force, a shearing force, an impact force, a pressure, and the like. It can be directly converted into light by the light emission of the material itself on which it acts, so it can be expected to have a wide range of applications such as the possibility of being used as an entirely new optical element.

[Brief description of drawings]

FIG. 1 is a graph showing a stress-luminescence behavior when a mechanical action force is applied to a pellet-shaped sample in Example 1.

FIG. 2 is a graph showing the stress dependence of the emission intensity of the pellet-shaped sample in Example 1.

Front page continuation (51) Int.Cl. ⁷ Identification code FI theme code (reference) C09K 11/64 CPR C09K 11/64 CPR 11/59 11/59 11/62 11/62 11/67 11/67 11 / 78 11/78 11/79 11/79 (72) Inventor Chou Xu, 807 Nonoshita, Nojishita, Yado-cho, Tosu City, Saga Prefecture, Kyushu Center, AIST (72) Inventor, Kazuhiro Nonaka 807 Nonoshita, Yado-machi, Tosu City, Saga Prefecture F-term in the National Institute of Advanced Industrial Science and Technology Kyushu Center (Reference) 4H001 CA04 XA04 XA08 XA11 XA12 XA13 XA14 XA19 XA20 XA25 XA30 XA38 XA40 XA41 XA56 XA57 XA58 XA73 YA YA24 YA25 YA26 YA27 YA28 YA29 YA41 YA42 YA58 YA59 YA60 YA61 YA62 YA63 YA64 YA65 YA66 YA73 YA74

Claims (4)

[Claims] 1. (A) General formula xM ¹ O.yAl ₂ O ₃ .zSiO ₂ (wherein M ¹ is Ca, Ba or Sr, and a part of them is at least Na, K and Mg). Aluminosilicate represented by the formula (1), x, y and z are numbers 1 or more), and (B) the general formula xM ² O · yAl ₂ O ₃ (wherein M ² is Ca or Ba, part of which is Mg
And La in which x and y have the same meanings as described above), and (C) a general formula xM ³ O.ySiO ₂ (wherein M ³ is Ca Or Sr, part of which is N
a, Mg, Zn, Be, Mn, Zr, Ce, and Nb may be substituted, and x and y have the same meanings as described above) or Ba ₂ Mg.
A silicate represented by SiO ₇ , (D) a general formula xM ⁴ O.yM ⁵ ₄ O ₁₁ (wherein M ⁴ is Ca, Ba or Sr, M ⁵ is Ta and Nb.
At least one of the above, wherein x and y have the same meanings as described above),
(E) General formula xM ⁵ O · yGa ₂ O ₃ (wherein M ⁵ is Ca, Ba or Sr, part of which may be replaced by La, and x and y have the same meanings as described above. And Zr
At least one selected from a rare earth metal or a transition metal that emits light when an electron excited by mechanical energy returns to a ground state in a base material made of at least one oxide selected from O _2. A mechanoluminescent material characterized by adding a luminescent center of a seed. 2. The mechanoluminescent material according to claim 1, wherein the rare earth metal and the transition metal have a first ionization energy of 8 eV or less. 3. The rare earth metal is Ce, Pr, Nd, Pm,
The mechanoluminescent material according to claim 1 or 2, which is at least one selected from Sm, Eu, Gd, Tb and Dy. 4. The transition metal is Ti, V, Cr, Mn, F.
The mechanoluminescence material according to claim 1 or 2, which is at least one selected from e, Co, Ni, Cu, Nb, Mo, Ta and W.